For a large telescope to follow or track stars, etc. as the earth rotates, telescopes have been mounted on support structures that continuously move the telescope about a polar axis which is substantially parallel to the earth's polar axis so that the rotation of the earth will not require continual readjustments of the telescope. In the past, the larger telescopes have been designed for and erected at permanent latitudinal locations because of their large size and weight and because of the difficulty of aligning and maintaining the polar axis of the telescope support assembly. The large telescope installations usually include a massive amount of metal and concrete for the purpose of anchoring and supporting the telescope and its various associated components in a permanent location.
While virtually all large telescopes can be moved with their support systems so as to rotate with respect to the earth's surface and change their angle of elevation to sight on and track various stars, etc., the telescopes are limited in that they cannot track an object near or below their horizon of the earth. This preludes the telescope from sighting on objects visible only at remote latitudes. Thus, even the most powerful, most accurate and most expensive telescope may be useless because of its permanent location if the object to be sighted happens to be inaccessible to the line of sight from the particular latitude on the earth at which the telescope is located. Moreover, on many occasions permanently mounted telescopes are rendered useless because of cloud coverage, air pollution or other local atmospheric conditions. Also, the precession and nutation of the earth necessitates frequent realignment of the polar axis of the telescope with the earth's polar axis, and the realignment process is delicate and onerous.